Method of making portland cement.



UNITED STATES PI'XTENT ()FFICE.

JOSEPH MAX'WELL CARRL ERE, 0F ALLENTOVJN, PENNSYLVANIA, ASSIGNOR TO BLANC STAINLESS CEMENT COMPANY, OF ALLENTOWN, PENNSYLVANIA, A CORPORATION OF NEW JERSEY.

METHOD OF MAKING PORTLAND CEMENT.

932, C37 4. No Drawing.

To all whom it may concern:

Be it known that I, JOSEPHlVIAXWELL pAR- 1: Emma citizen of the United States, residing at Allentown, county of Lehigh, State of Iennsylvania, have invented certain new and useful Improvements in Methods of Making Portland Cement, of which the following is a full, clear, and exact description.

My invention relates to improvements in the manufacture of Portland cement, and has for its object to produce a new and improved process whereby Portland cement of superior quality is produced at a relatively low temperature.

A further object of my invention is to produce Portland cement at such a temperature, which cement shall be White or lightin color, and also have the property of not staining the most delicate stone or become discolored itself.

The following is a description of an embodiment of my invention, its subject matter being hereinafter definitely pointed out in the claims.

In practicing my invention in the preferred form, I together the following in gredicnts:lime in the form of carbonate of lime seventy-three (73) parts, a silicious material in the form of clay or shale twenty-two (22) parts, and a zinc corn )ound in the form of carbonate of zinc five (5 parts. In order that the cement should be white or light in color, all these ingredients should be free from iron and other impurities, such as sulfur and the like. These ingredients are -first thoroughly mixed andgro'und in the proporare then burnede o'l'ore employed auhc or Portland tions above specified; a in the ordinary manner, he in the manufacture of by cement. and very greatly reduces the degree of heat necessary to clinker. After the mixture has been subjected to a sufficient degree of heat to clinker, it is then pulverized in the ordi nary manner and is'ready for shipment for ordinary uses without the addition of any; If it is desired to make it set still" retarder. more slowly, a retardcr such as sulfate of lime canbe added.-

Other compounds of zinc may be used in place of carbonate of zinc, suchfo-i' instance as silicate of zinc, alumuiateof zinc or zinc OXl(l, but in such case due allowance must be Specification of Letters Patent.

Application fi-led August 27, 1907.

The carbonate ofzinc acts as a flux Patented Aug. 24, 1909.

Serial No. 390,413.

made for the difference in the elements combined with. the zinc and the proportions would preferably be somewhat different from those above specified. The compounds of zincabove referred to are found in a state of nature as smithsonite (ZnCfi calomi'ne gahnite (Zn [A10 and zincite (ZnO).

The proportions in the mixture above named have been found by me to produce satisfactory results. The mixture fuses at a much lowecdegree of heat than hasheretofore been necessary in connection with the commercial manufacturev of Portland eement, and produces a product which, when hardened, is practically White, and moreover does not change in color and does not stain or discolor stone, brick, or similar materials with which it is brought in contact;

By reason of theuse of a zinc compound as a flux, I am enabled to substitute for the clay ordinarily used in the manufacture of Portland cement, substantially pure silica as found in various forms, for instance, sand, sandstone or decomposed sandstone. When silica is used, I 'preferto use the following proportions :carbonate of lime seventyseven (77) parts, silica eighteen (18) parts,

carbonate of zinc five (5) parts. This Inixor shale, above-referred to, I have based the same on substantially pure carbonate of lime, and pure clay or shale; Limestoncs and clays or shales vary in proportions of the carbonate of lime and silica that each. con-- turns, and with difiering limestones and clays the roportions I have named for the mix .wou d have to be varied accordingly to obtain in the mix the correct proportions of lime .and silica for the bestcement. The lin1estone which I use is obtained from the Ann rille, Pennsylvania, regions and contains about ninety-seven (97) or ninety-eight (98) per cent. of carbonate of lime. The clay is obtained from Minesite, Pennsylvania, and

contains about sventy-five (775) per cent. of silica and less than two (2-) per cent. o'l'car bonate of lime.

c hat I claim is: .1+

: 1. The improvement in the process of manufacturing Portland cement, \fliich corsists in mixing with lime and a silicious material, a zinc compound and then burning the mixture and pulverizing the clinker.

2. The improvement in the process of manufacturing, Portland cen.ent, which consists' in mixing with lime and a silicious ma terial, a salt of zinc, and then burning the mixture and pulverizing the clinkerproduced thereby.

3. The improvement in the process of manufacturing Portland cement, which consists in mixing with lime and a silicious material, carbonate of zinc, burning the same and then pulverizing the clinker produced thereby. i

4. The improvement in the process of manufacturing Portland cement, which consists in producing a mixture of carbonate of lime, a silicious material, and carbonate of zinc, burning the same and pulverizing the clinker produced thereby.

5. The improvement in the process of making a White, stainless cement, which consists in l'ormin; a mixture of carbonate of lime, a 'silicious material and a salt otwzinc, all being free from iron, burning the same and pulverizingthe clinker produced thereby.

6. The improvement in the process of -manufacturing Portland celtuau, which consiat's in )roduciuga inixlureol' carbonate ot lime, substantially pure silica, and carbonate of Y.inc,-,burnin the same and pulverizingr the clinker produced thereby.

8. The improvement in the process of 'manufacturing Portland cement, which consists. in mixing} a quz'llntity of lime with a smaller quantity ol' silicious material, and a still smaller quantity o't burning the mixture, an clinker produced thercbyl JOSEPH J] txwumi (uremia zinc compound, l" pulverizing' the Vi itnesses:

ll. B. Buon'xurt, Laxonox Bloom: 

